internal/task/releaselet: add logging to MSI building
internal/task/releaselet: add logging to MSI building

Building the MSIs can take quite a while. Add some logging to keep the
watchdog happy.

For golang/go#54134.

Change-Id: I6178323f6e34a6ecd409370e9e396f683a6cdb9f
Reviewed-on: https://go-review.googlesource.com/c/build/+/420542
Reviewed-by: Jenny Rakoczy <6a3f4389a53c889b623e67f385f28ab8e84e5029@golang.org>
Run-TryBot: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>
Auto-Submit: Heschi Kreinick <e89ab2b172855aa0ad01c40c4d8a3535a61ac68a@google.com>
TryBot-Result: Gopher Robot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>

golang/build,golang/build,golang/build,golang/build